Welded Helical Solid Finned Tubes manufactured with by helically wrapping fin strip on edge around the tube circumference and continuously welding the fin strip to the tube. the use of high-frequency current skin effect and proximity effects, the steel and steel pipe surface heating, until the plastic state or melting, in the winding strip under a certain pressure Completed solid phase welding.The fin strip is held under tension and confined laterally as it is formed around the tube, thereby ensuring that the strip is in forceful contact with the tube surface.

Can be used for practically any heat transfer application, and is particularly suited to high temperature, high pressure applications with high fin-side temperatures. Solid fin can be supplied with thicker fins than the serrated fin, which can be an important factor when dealing with extremely corrosive or erosive environments.

Welded spiral fin tubes ( fin tubes ), is a highly efficient heat transfer components. Its heat transfer area of the optical tubes (pipes) several times or more, enhanced heat transfer, reducing the flow resistance, reducing the metal consumption, thus improving the economy and operational reliability of the heat transfer equipment. At present, high frequency welded helical (spiral) fin tubes has been widely and has been widely used in a variety of chemical, electric power, metallurgy, petrochemical, boiler, building materials, textile, environmental protection, dry, medical field.

Available tubes /pipe material for fin tubes:

fin material: carbon steel, corrosion-resistant steel, stainless steel, alloy steel, copper

welding finned forms: real teeth, opened teeth(serrated fin tubes)

general used materials:

Supply Range of base tubes (pipes) (core tube): Carbon Steel ASTM A 179, ASTM A 192, ASTM A 210 Gr. A1, ASTM A 210 Gr. C, ASTM A 106 Gr. B

Low Alloy Steel ASTM A 209 T1, ASTM A 213 / A 199 T11/T12, ASTM A 213 / A 199 T22, ASTM A 213 / A 199 T5, ASTM A 213 / A 199 T9, ASTM A 335 P1 / A 161 T1, ASTM A 335 P11 / P12 / A 200 T22, ASTM A 335 P22 / A 200 T22, ASTM A 335 P5 / A 200 T5, ASTM A 355 P9 / A 200 T9

Stainless Steel ASTM A 213 / A 312 TP 304l, ASTM A 213 / A 312 TP 304L, ASTM A 213 / A 312 TP 321, ASTM A 213 / A 312 TP 316, ASTM A 213 / A 312 TP 316L, ASTM A 213 / A 312 TP 347, ASTM A 213 / A 312 TP 316Ti, ASTM A 289 / A 790 UNS S 31803, ASTM B 677 Alloy 904L

Nickel ASTM B 161 Ni 200, ASTM B 161 Ni 201

Copper tubes

General Manufacturing Process: The fin strip is welded continuously and spirally wound onto a polished bare tube. And the tube and fins are bonded together by using high frequency resistance welding technique.

We produce both solid plain and serrated helical welded steel finned tube. And also, all spiral welding tubes could be bent in the middle or at the end of fin tubes, we call it Hairpin tubes.

SA192 Seamless carbon steel tubes, high frequency resistance welded fin tubes with solid or serrated fins

Additional Services for Solid helical welded fin tubes:

High frequency welding machine output power supply: 200KW or 300KW

The High Frequency Resistance Welded Spiral Fin Tube quality is assured by hydrostatic or pneumatic tests and tensile tests in order to verify the mechanical bonding between bare tube and fin materials.

Acceptance criteria: INTERNATIONAL STANDARD FOR DIMENSIONS, TOLERANCES, AND TESTS OF HIGH FREQUENCY RESISTANCE WELDED FINS or the delivery conditions (TDC) of clients.

Visual check: un-welded parts of fin, fin damage after fining, copper pollution, tears, wrap etc…

Dimensional check: fin height, fin spacing, fin inclination, fin corrugation, length of finned & un-finned portion etc…

Bending check: ovality, thickness and area reduction.

Coating: outside-Red oxide zinc phosphate primer and inside volatile corrosion inhibitor (VCI) in water soluble tablet form.

Fin end finish: Bevel(30~35degeree)

Delivery condition: Tube ends are square cut, free burrs, internally dried and air blown clean, externally coated with varnish at both ends of helical welded tubes. The desiccants are put into the each package for continental transportation as well.

Documentation shall include QAP, WPS, PQR& WPQ, raw materials mill certificates, inspection and test samples results and warranty certificate of manufacturer.

Applications:

The High Frequency Resistance Welded Helical Fin Tubes are widely applied in fired heaters, heat exchanger, boilers, economizers, pre-heaters, coolers, heat pipes, heaters etc….

SA192 Seamless carbon steel tubes, high frequency resistance welded fin tubes with solid or serrated fins

Specifications:

A wide range of fin and tube materials could be combinations are available.

Items General Materials   Popular ASTM  Materials

Core Tube Material

Carbon Steel , Alloy Steel, Heat Resistant Steel,

Stainless Steel etc.

10#,20#,15CrMo,Cr5Mo,Cr9Mo,1Cr18Ni9Ti,0Cr18Ni9,00Cr17Ni14Mo2,SA106B,SA106C, SA192, SA179,                    

SA178,SA214, SA210-A1, SA210-C,TP304/304L/304H,               TP409/410,TP316/316L,TP321/321L,TP347H,T11,T22,T91,etc.           

Fins Material  

Carbon Steel , Alloy Steel, Heat Resistant Steel,

Stainless Steel etc.

Q235-BF,08F,08AL, 1Cr18Ni9Ti, 0Cr13, 1Cr13, 0Cr18Ni9, 09CrCuSb, CS,A1008-B,SPHC, SPCC, TP304/304L,TP316/316L,TP321/321L,etc.

Additional supply range :

(1) Tube swaging process for joint of 2 tubes.

(2) Spacer rings (material: steel) are available.

(3) One side is solid plain fins and the other is serrated fins, 2 fin types on same tube.

Competitive Advantage:

We have more than 10,000 square meters workshop, including 4 ERW high Frequency welding fining lines, daily production capacity around 40 Tons;

Our quality assurance plan for High Frequency Welding Spiral Steel Tubes.  (2.1) Raw material control for both plain tubes and fins. (2.2) In process control with reports,as WPS, PQR&WPQ; weld deposition efficiency test before fabrication, Non-destructive test and tensile test etc. (2.3) Final inspection control with reports (Visual and dimensional check etc…).

The High Frequency Resistance Welded Fin Tube is integrally extended for the max surface area to achieve efficiency. The heat transfer ratio of high frequency welding fin tube is about 8~9 times higher than other plain tubes.

This Welded Helical Fin Tubes is a singular integral unit, eliminating heat contact resistance and losses. Generally tube side temperature up to 800 degree for stainess steel fins; Low carbon steels, withstanding up to 475 degree is the most common choice.